DEPARTMENT OF ENVIRONMENTAL QUALITY

WATER DIVISION

MEMORANDUM

P. 0. Box 10009 Richmond, VA 23240-0009

SUBJECT: OWRM Program Guidance Memorandum No. 94-012 Calcium Carbonate Equivalence (CCE) Testing Requirement

TO: Regional Directors

FROM: Larry G. Lawson, P.E. Director, Office of sourc s Management

DATE: October 20, 1994

COPIES: Bob Burnley, James Adams, Martin Ferguson, Regional Office Permit Managers, Ron Gregory, OWRM Permit Staff

The purpose of this memo is to correct the confusion resulting from the CCE and Alkalinity reporting requirements in VPA Permit Application Forms C and D, and in a few recently issued VPA permits.

Detailed background information is provided through the attached memo from Lily Choi to Dale Phillips dated September 23, 1994.

In order to resolve the aforementioned issues, the following recommendations are provided:

1. VPA Form C and Form D. CCE as a separate parameter should be eliminated (by simply marking through it) from the waste characterization list for sludge analysis. Alkalinity will continue to be required as a screening parameter and will retain the footnote requiring CCE testing for sludges containing more than 10% lime (dry weight). CCE testing should be run by following the methodology in Attachment A.

2. VPA Permit. CCE monitoring, per attachment A, should not be required routinely in the permit unless review of the application indicates that the sludge is expected to contain a lime content of 10% (dry weight) or more.

DEPARTMENT OF ENVIRONMENTAL QUALITY WATER DIVISION

OFFICE OF WATER RESOURCES MANAGEMENT

MEMORANDUM

P. 0. Box 10009 Richmond, VA 23240-0009

SUBJECT: Calcium Carbonate Equivalence (CCE) Testing Requirement

TO: Dale Phillips

FROM: Lily

DATE: September 23, 1994

COPIES: Martin Ferguson, Fred Holt, Richard Ayers

The purpose of this memo is to address the confusion resulting from the CCE and Alkalinity reporting requirements in VPA Permit Application Forms C and D, and in a few recently issued VPA permits.

Some laboratories do not distinguish between the methods in Attachment A (CCE) and Attachment B (Alkalinity) and may report identical results for both parameters.

However, the titration end point for alkalinity can be as low as pH 4.5. The titration end point for the CCE testing can be as high as pH 8.3 in accordance with the indicator titrimetric method which is commonly used by the commercial labs. Obviously, the reported results will be dramatically different.

CCE represents a "true" acid-neutralizing capacity when agricultural liming is of concern. Besides the fact that natural soil in Virginia is already in an acidic condition, an acidic soil environment is generally expected when nitrogen enriched sludge is land applied. This is due to the release of hydrogen ions through nitrification. Therefore, liming is part of soil amendment procedures.

It should be recognized that, generally, the CCE testing methodology is only reliable for materials containing significant amounts of lime (>10% CaCO3), such as lime treated sludges (mainly sewage sludge). Negative values may be reported if the test is run for low or zero lime materials (such as aerobically digested sludge or water treatment coagulation sludge). For example, two water treatment plant sludges have been required to run CCE per their permit requirements and negative values have been reported. Both sludges exhibit low alkalinity values (0.1% and 2.3% CaCO3 respectively).

Alkalinity measurements are often used in the interpretation and control of water and wastewater treatment processes. Alkalinity testing results do not provide much meaning for land application of sludges. However, it continues to be a valid screening parameter to detect those sludges that may contain a high lime content, and subsequently to assess the maximum allowable sludge loading based on its lime content. This is especially critical for coastal plains soil where micronutrient deficiencies could occur due to overloading, or high pH conditions. The liming effect of a proposed sludge should be assessed by reviewing the CCE testing results, coupled with the exhibited pH values and the treatment processes employed.

- 1 - 92 WED 1 1= 4 Z 1=' - 0 2

,\LI//171-14-r

OFFICIAL . OF ANALYSIS:

OF THE

ASSQCIATION OF OFFICIAL ANALYTICAL CHEMISTS

Emit() BY KENNETH HELRICH

FIFTEENTH EDITION. 1990

PuBLISHED BY THE

ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS, INC.

SUITE 400

2200 WILSON BOULEVARD

ARLINGTON. VIRGINIA 22201 USA

k4. •••• • • 924.01 . • • Sampling of Liming Materials

: . • -S:".• • * :Procedure •

*.•-• • • • • (Cautlott see safety nett on calcium oxide.)

. • z.; Take l•

iainPle:repreicatiitti,c/Of iot or shipment...A.voll. 1 ••••: • • • • it :amt of surface or airy modified or daritaged zone. • •

(a) Burnt or lumio little. la bulk. —collect composite ssaammpple : of 10, shovelfuls/0i.; with* prciportionat iirntsfropa spa ler

• • : • - 100 ,..taking • each Shovelful from alas- • • rack.. Immediately crush* 44:•C.iruk.*

Fr'.1-* • ':: opening: mix litnrolY. and iarlidly;'..nid4ce .#‘

ea 2 i.".* • . 7 • kg (5 lb) 'simple by riffling or Quartering;; and place in labeled,

.. • thy; air-tightcontamcr. • . • ., • . • • •.• •• • • . (b) Hydrated lithe and lime; in thys.--Scleat 10 bait fromdiffereni parts of each foi:or.shipMent of 20

..:••••• tonsisnd 1 added bag for'cae 'h • s•dd nt 5 tons. Usc siubpling tube • -• to withdrvi fog, :to ttegicifii fioniastell berg sclectesl. Coni-

bnA•co.v#, ;;T:Ox jt:&1:-Ko *OoiliPotit to ca: kg a 10 briitiling or sitartering, and place in dry, air-tight

•.•

• • container. • • •

' (6) Gionild limestone and ground marl, in bags.—Procced as 1R (b), . • •

. (0).Grolo.4.11njOione, ground burnt lime, round marl. and sidg, slotted sampling tube, to withdraw samples to Nil saftiip fer dead* frOU.10 points in lot .or 0‘ipmiint. Pm-coed as is (b), beginning "Combinc"cords, ':••

ftCf:S.; /•AOAC 7, 252:(1924); 48, 95(1965);

CAS-1311.65-3 (limestone) • •

•:•••

• • • -• :

•

ce44.02 Mechanical Analysis of Liming Materials

PreeedUrs

• (Caution: .Sec safety note on calcium oxide.) • If entiro sample is not to be dried, obtain lesser portions by

riffling or Quartering. Dry at 110° to const wt and cool to room

-Obtain 90-150 g dry sample by riffling or quartering. Break airy aggionitrates formed during drying by tolling, dry wimple with hard rubber rollti'On tiara rubber mat, Wet sieving, or by

does' not result in cnishine the • • •• .•

*Wel 100 g Sample on No. 200 sieve and wash. with ;Moderate strewn* of tap H2O at max. gage prcs.s-ure 6;i6.2.84/sq cni (41b/sq in.).Until H2O passing sieve is clear, with •care.tO avoid 101 of sample by- sphisliing: Dry material reiriaining on sic.ve 'et l05° and transfer to ),16. 100 sieve in . . siijc3 with No. 200 slovo of earn diam. and depth,. Shake 8 min in mech. shaker. (if wet sieving is used to break agglom-• 0:Mts. do ivet sieving on sieve having smallest opening to be used is final testing. After drying, transfer to sieves to be used in final icliting. If only 1 sieve is•to.bensed; do not transfer.) OuiliAt.'tintisierwelghRdatiirtOle-td ediam. sleVo or sot of

g ` . • •. 10, sieves (6 "Nes' 20, .60,80, 40 and 100 or other sp- .., .1itopritite combination). .

F, _ 0

. •.•

Sieve by lateral and vertical motion accompanied by jarring action. Continua: i5 Min Of.tintifiddid _3 min of sieving ••• fails to chaligcresnitKof any siaVefraction.bY 0.512.of sample C(t; Do. not o*loarl any sic* when assaying closely lit#4 ` • " •

Dot. wt of each sieve fraction and report as % of total plc wt.

Refs.: JAOAC 7, 252(1924); 55, 539(10.2); 48, 9.5(1905Y; 3220969). • • • • .: -; •

924.03

Lltrilnd Materials • 3:. i• Preparation • . •••

• OnocedUia4,* • • ••• •

Rectuce dried.saMptc, 924.02, to unit sufficient foi; nnitlYsJS•;. and grind t22.5 g (0.5 lb) reduced.sarnple'iritneitir; hall mill; • • •• or other =oh. app. to pass No. 60 sieve. Mix tit441y, and. • store in air-tight container.

Refs.: SAOAC 7, 232(1924); 48, 95(1965).

955.01 Neutralizing Value • • for Liming Materials

Final Action • • • • • • .

(Uncorrected for sulfide content)

A. Reagents (a) Sodium hydroxide std soln,-0.25N. Prep. and Sid= as .

in 936.16. (b) Hydrochloric acid std soln.-0.5N. Stdzc against (a),

using phdiln. 8. Indicator Mr/metric Method • • •

Place 0.5 g burnt or hydrated lime (1 g ground lirnesiOne•or . ground mad), prepd as in 924.03, in 250 rnL crienthey.erCadd 50 mi.. HCI std soln and boil gently. 5 Cool, and air.• . excess acid with NaOH std sots, using phthin.. rot buirit.snd. hydrated lime, report as % Ce0; for limestone andniarl;repert; as % CliCO3 equivalonoo. tai

44, CaCO3 equivaleneo of sample • • .

2.5 x (mL 110 mL NaOH/2); • % CaO equivalence •I 2.8 x (mL 1iC1 — mL NnOt4/2). .

C. Potent/metric Titration Method (Applicable to liming materials contg large Milt of 1"e29r CO1-

oring matter, but not to •silicatC materials). •••••

Proceed as in 955.0113 thru "Cool, . trunsref to 250, mL beaker and insert glass and calomel electrodes of PH Me-ter, buret contg '0.25N NaOH, and mcch. stirrer. Stir at mod-crate speed to avoid splash. Deliver NaOH r pid1y t.0441 5, . then dropwise until sole attains pH 7 •and remains Const 1 min while batting,. Of end point Is passed: add,Ircisn tit* • pipet, just enough 0.5N HCl to bring phi to <7-, andbaCk-itier. • slowly to pH 7.) Add mt.. of excess acid, if used.,to1ilitini.56

t4o •••;." — 1 S-92 WED 11 = 44

:

•

AgriOltural Liming . Materials . •

Fr4ik 'JOhrison Associate Chapter Editor' . . . .Center,

•:: National Fertilizer pei,eloritreht Tennessee Valley Authority

.. ,

'1;-frx-ride.„.coPie<wi let4t/4'-havi 1q9

ALKALINITY (2320)/Introduction 2-25 /67 /4a1,71-7/

increments of 0.02N sulfuric acid (H,S0,) (Section 2320B.3c) to reduce pH to 4 or less. Remove electrodes. Add 5 drops 30c/c. 1-120,, and boil for 2 to 5 min. Cool to room temperature and titrate with standard alkali to pH 8.3 according to the procedure of 4d.

b olor change: Select sample size and normality of titrant accord, to criteria of II le. Adjust sample to room temperature. if necessa and with a pipet discharge sample into an erlen- meyer flask. w "le keeping pipet tip near flask bottom. If free residual chlorine is .resent add 0.05 mL (1 drop) 0.1M Na2SzO: solution, or destroy " h ultraviolet radiation. Add (1.2 mL (5 drops) indicator solution d titrate over a white surface to a persistent color change char eristic of the equivalence point. Commercial indicator solutions • solids designated for the ap-propriate p1-1 range (3.7 or 8.3) may • used. Check color at end point by adding the same concentration indicator used with sample to a buffer solution at the designate H.

c. Potentiometric titration curve: 1) Rinse electrodes and titration vessel with distil • water and

drain. Select sample size and normality of titrant acc ding to the criteria of 9le. Adjust sample to room temperature. t ec-essary, and with a pipet discharge sample while keeping pip tip near the titration vessel bottom.

2) Measure sample pH. Add standard alkali in increments o 0.5 mL or less, such that a change of less than (1.2 p1-1 units o • rs per increment. After each addition, mix thoroughly bu gently with a magnetic stirrer. Avoid splashing. Record when a constant reading is obtained. Continue adding tit nt and meas-ure pH until pH 9 is reached. Construct the ration curve by plotting observed pH values versus cumuli •ve milliliters titrant added. A smooth curve showing one or tore inflections should he obtained. A ragged or erratic cu •e may indicate that equi-librium was not reached between ccessive alkali additions. De-termine acidity relative to a p icular pH from the curve.

d. Potentiometric titratiot o pH 3.7 or 8.3: Prepare sample and titration assembly a specified in Titrate to prese- lected end-point pH Id) without recording intermediate pH values. As the end oint is approached make smaller additions of alkali and be s e that pH equilibrium is reached before wak-ing the next a • Mon.

5. Cale .tion

Acidity. as mg CaCO /L 3 1(A x B) — (C x D)1 x 511 (10()

mL sample

where: A = mL NaOH titrant used. B = normality of NaOH, C = mL 1-12S0, used (I 4a). and D = normality of H,S0,.

Report pH of the end point used, as follows: "The acidity to pH = mg CaCO/L." If a negative value is obtained. determine the alkalinity according to Section 2320.

6. Precision and Bias

No general statement can be/nade about precision because of the great variation in sample-tharacteristics. The precision of the titration is likely to be much greater than the uncertainties in- volved in sampling sample handling before analysis.

Forty analysts.iti 17 laboratories analyzed synthetic water sam-ples containing increments of bicarbonate equivalent to 20 mg CaCOIL!Titration according to the procedure of ¶ 4d gave a Stan id deviation of 1.8 mg CaC0/1.., with negligible bias. Five

ratories analyzed two samples containing sulfuric. acetic, and ormic acids and aluminum chloride by the procedures of Is 4b

and 4d. The mean acidity of one sample (to pH 3.7) was 487 mg COIL, with a standard deviation of 11 mg/L. The bromphenol

blue 'tration of the same sample was 90 mg/L greater. with a standar• deviation of 110 mg/L. The other sample had a poten-tiometric t ation of 547 mg/L, with a standard deviation of 54 mg/L, while •e corresponding indicator result was 85 mg/L greater. with a s dard deviation of 56 mg/L. The major dif-ference between the amples was the substitution of ferric am- monium citrate, in the •nd sample, for part of the aluminum chloride.

7. Bibliography

WINTER. J.A. & M.R. MiocErr. 1969. FWP Method Study I. Min- eral and Physical Analyses. Federal Water lution Control Ad- min.. Washington. D.C.

BROV.,N. E.. M.W. SKOUGSTAD FISHMAN. 1970 Methods for collection and analysis of water samples for dissolved minerals and gases. Chapter Al in Book 5. Techniques of Water-Resources In-vestigations of United States Geological Survey. U.S. Geological Survey. Washington. D.C.

SNOEYINK. & D. JENKINS. 1980. Water Chemistry. John Wiley & Sons. New York. N.Y.

2320 ALKALINITY*

2320 A. Introduction

1. Discussion

Alkalinity of a water is its acid-neutralizing capacity. It is the sum of all the titratable bases. The measured value may vary

Approved by Standard Methods Committee. 1991.

significantly with the end-point pH used. Alkalinity is a measure of an aggregate property of water and can be interpreted in terms of specific substances only when the chemical composition of the sample is known.

Alkalinity is significant in many uses and treatments of natural waters and wastewaters. Because the alkalinity of many surface

2-26

PHYSICAL & AGGREGATE PROPERTIES (2000)

waters is primarily a function of carbonate, bicarbonate, and hydroxide content, it is taken as an indication of the concentra-tion of these constitutents. The measured values also may include contributions from borates. phosphates, silicates, or other bases if these are present. Alkalinity in excess of alkaline earth metal concentrations is significant in determining the suitability of a water for irrigation. Alkalinity measurements are used in the interpretation and control of water and wastewater treatment processes. Raw domestic wastewater has an alkalinity less than, or only slightly greater than, that of the water supply. Properly

operating anaerobic digesters typically have supernatant alka-linities in the range of 2000 to 4000 mg calcium carbonate (CaCO3)/L.'

2. Reference

1. POHLAND. F.G. & D.E. BLOODGOOD. 1963. Laboratory studies on mesophilic and thermophilic anaerobic sludge digestion. J. Water Pol-lut. Control Fed. 35:11.

2320 B. Titration Method

1. General Discussion

a. Principle: Hydroxyl ions present in a sample as a result of dissociation or hydrolysis of solutes react with additions of stand-ard acid. Alkalinity thus depends on the end-point pH used. For methods of determining inflection points from titration curves and the rationale for titrating to fixed pH end points, see Section 2310B. la.

For samples of low alkalinity (less than 20 mg CaCO3/L) use an extrapolation technique based on the near proportionality of concentration of hydrogen ions to excess of titrant beyond the equivalence point. The amount of standard acid required to re-duce pH exactly 0.30 pH unit is measured carefully. Because this change in pH corresponds to an exact doubling of the hydrogen ion concentration, a simple extrapolation can be made to the equivalence point.'

b. End points: When alkalinity is due entirely to carbonate or bicarbonate content, the pH at the equivalence point of the titration is determined by the concentration of carbon dioxide (CO') at that stage. CO, concentration depends, in turn, on the total carbonate species originally present and any losses that may have occurred during titration. The pH values in Table 2320:I are suggested as the equivalence points for the corresponding alkalinity concentrations as milligrams CaCO3 per liter. "Phen-olphthalein alkalinity" is the term traditionally used for the quan-tity measured by titration to pH 8.3 irrespective of the colored indicator, if any, used in the determination. Phenolphthalein or

TABLE 2320:1 END-POINT PH VALUES

End Point pH

Test Condition

Total Alkalinity

Phenolphthalein Alkalinity

Alkalinity. mg CaCO3/L:

30 4.9 8.3 150 4.6 8.3 500 4.3 8.3

Silicates. phosphates known or suspected 4.5 8.3

Routine or automated anal-yses 4.5 8.3

Industrial waste or complex system 4.5 8.3

metacresol purple may be used for alkalinity titration to pH 8.3. Bromcresol green or a mixed bromcresol green-methyl red in-dicator may be used for pH 4.5.

c. Interferences: Soaps, oily matter, suspended solids, or pre-cipitates may coat the glass electrode and cause a sluggish re-sponse. Allow additional time between titrant additions to let electrode come to equilibrium or clean the electrodes occasion-ally. Do not filter, dilute, concentrate, or alter sample.

d. Selection of procedure: Determine sample alkalinity from volume of standard acid required to titrate a portion to a des-ignated pH taken from l lb. Titrate at room temperature with a properly calibrated pH meter or electrically operated titrator. or use color indicators. If using color indicators, prepare and titrate an indicator blank.

Report alkalinity less than 20 mg CaCOIL only if it has been determined by the low-alkalinity method of 9 4d.

Construct a titration curve for standardization of reagents. Color indicators may be used for routine and control titrations

in the absence of interfering color and turbidity and for prelim-inary titrations to select sample size and strength of titrant (see below).

e. Sample size: See Section 2310B. le for selection of size sam-ple to be titrated and normality of titrant, substituting 0.02N or 0.1N sulfuric (1-1„SO.,) or hydrochloric (HC1) acid for the standard alkali of that method. For the low-alkalinity method, titratc a 200-mL sample with 0.02N H,S0, from a 10-mL buret.

f. Sampling and storage: See Section 2310B.lf.

2. Apparatus

See Section 2310B.2.

3. Reagents

a. Sodium carbonate solution, approximately 0.05N: Dry 3 to 5 g primary standard Na2CO3 at 250°C for 4 h and cool in a desiccator. Weigh 2.5 ± 0.2 g (to the nearest mg), transfer to a 1-L volumetric flask, fill flask to the mark with distilled water. and dissolve and mix reagent. Do not keep longer than 1 week.

b. Standard sulfuric acid or hydrochloric acid. 0.1N: Prepare acid solution of approximate normality as indicated under Prep-aration of Desk Reagents (see inside front cover). Standardize against 40.00 mL 0.05N Na,CO, solution. with about 60 mL water, in a beaker by titrating potentiometrically to pH of about 5. Lift out electrodes, rinse into the same beaker. and boil gently

7

ALKALINITY (2320)/Titration Method 2-27

for 3 to 5 min under a watch glass cover. Cool to room temper-ature, rinse cover glass into beaker, and finish titrating to the pH inflection point. Calculate normality:

A x B Normality. N —

53.0(! x C

where: A = g Na,CO, weighed into 1-L flask. B = mL Na,CO, solution taken for titration. and C = mL acid used.

Use measured normality in calculations or adjust to 0.1000N: 1 mL 0.1000N solution = 5.(X0 mg CaCO3.

c. Standard sulfuric acid or hydrochloric acid. 0.02N: Dilute 200.00 mL 0.1000N standard acid to 1000 mL with distilled or deionized water. Standardize by potentiometric titration of 15.00 mL 0.05N Na.00x according to the procedure of 1 3b: 1 mL = 1.00 mg CaCO3.

d. Broincresol green indicator solution, pH 4.5 indicator: Dis-solve 100 mg bromcresol green, sodium salt, in 100 mL distilled water.

e. Mixed bromcresol green-methyl red indicator solution:3 Use either the aqueous or the alcoholic solution:

I) Dissolve 100 mg bromcresol green sodium salt and 20 mg methyl red sodium salt in 100 mL distilled water.

2) Dissolve 100 mg bromcresol green and 20 mg methyl red in 100 mL 95% ethyl alcohol or isopropyl alcohol.

f. Metacresol purple indicator solution, pH 8.3 indicator: Dis-solve 100 mg metacresol purple in 100 mL water.

g. Phenolphthalein solution, alcoholic. pH 8.3 indicator. h. Sodium thiosulfate, 0.1N: See Section 2310B.3i.

4. Procedure

a. Color change: See Section 2310B.4b. b. Potentiontetric titration curve: Follow the procedure for de-

termining acidity (Section 2310B.4c). substituting the appropri-ate normality of standard acid solution for standard NaOH. and continue titration to pH 4.5 or lower. Do not filter. dilute, con-centrate. or alter the sample.

c. Potentiontetric titration to preselected pH: Determine the appropriate end-point pH according to 1 lb. Prepare sample and titration assembly (Section 2310B.4c). Titrate to the end-point pH without recording intermediate pH values and without undue delay. As the end point is approached make smaller additions of acid and be sure that pH equilibrium is reached before adding more titrant.

d. Potentiontetric titration of low alkalinity: For alkalinities less than 20 mg/L titrate 100 to 200 mL according to the procedure of 14c, above, using a 10-mL microburet and 0.02N standard acid solution. Stop the titration at a pH in the range 4.3 to 4.7 and record volume and exact pH. Carefully add additional titrant to reduce the pH exactly 0.30 pH unit and again record volume.

5. Calculations

a. Potentiontetric titration to end-point pH:

A x N x 50 000 Alkalinity. mg CaCOA. —

mL sample

where: A = mL standard acid used and N = normality of standard acid

or

A x t x 1000 Alkalinity. mg

CaCOVL — mL sample

where: = titer of standard acid. mg CaCO3/mL.

Report pH of end point used as follows: -The alkalinity to pH = mg CaC0„/L- and indicate clearly if this pH corresponds to an inflection point of the titration curve.

b. Potentiontetric titration of /0 IV alkalinity:

Total alkalinity. mg CaCOJL

(2 B — C) x N x 50 000 mL sample

where: B = mL titrant to first recorded pH. C = total mL titrant to reach pH 0.3 unit lower. and N = normality of acid.

c. Calculation of alkalinity relationships: The results obtained from the phenolphthalein and total alkalinity determinations of-fer a means for stoichiometric classification of the three principal forms of alkalinity present in many waters. The classification ascribes the entire alkalinity to bicarbonate. carbonate. and hy-droxide. and assumes the absence of other (weak) inorganic or organic acids, such as silicic, phosphoric, and boric acids. It further presupposes the incompatibility of hydroxide and bicar-bonate alkalinities. Because the calculations are made on a stoi-chiometric basis, ion concentrations in the strictest sense are not represented in the results, which may differ significantly from actual concentrations especially at pH > 10. According to this scheme:

1) Carbonate (CO,' ) alkalinity is present when phenol-phthalein alkalinity is not zero'but is less than total alkalinity.

2) Hydroxide (OH- ) alkalinity is present if phenolphthalein alkalinity is more than half the total alkalinity.

3) Bicarbonate (HCO, ) alkalinity is present if phenolphtha-lein alkalinity is less than half the total alkalinity. These rela-tionships may be calculated by the following scheme, where P is phenolphthalein alkalinity and T is total alkalinity (II lb):

Select the smaller value of P or (T— P). Then, carbonate al-kalinity equals twice the smaller value. When the smaller value is P. the balance (T-2P) is bicarbonate. When the smaller value is (T— P). the balance (2P— 7-) is hydroxide. All results are ex-pressed as CaCO„. The mathematical conversion of the results is shown in Table 2320:11. (A modification of Table 2320:11 that is more accurate when P = 112T has been proposed.')

Alkalinity relationships also may be computed nomographi-cally (see Carbon Dioxide, Section 4500-CO„). Accurately meas-ure pH, calculate OH- concentration as milligrams CaCO, per liter, and calculate concentrations of CO,' - and HCO3 - as mil-ligrams CaCO„ per liter from the OH concentration, and the phenolphthalein and total alkalinities by the following equations:

ALKALINITY

Method 310.1 (Titrimetric, pH 4.5)

STORET NO. 00410

1. Scope and Application 1.1 This method is applicable to drinking, surface, and saline waters, domestic and industrial

wastes. 1.2 The method is suitable for all concentration ranges of alkalinity; however, appropriate

aliquots should be used to avoid a titration volume greater than 50 ml. 1.3 Automated titrimetric analysis is equivalent.

2. Summary of Method 2.1 An unaltered sample is titrated to an electrometrically determined end point of pH 4.5.

The sample must not be filtered, diluted, concentrated, or altered in any way.

3. Comments 3.1 The sample should be refrigerated at 4°C and run as soon as practical. Do not open

sample bottle before analysis. 3.2 Substances, such as salts of weak organic and inorganic acids present in large amounts,

may cause interference in the electrometric pH measurements. 3.3 For samples having high concentrations of mineral acids, such as mine wastes and

associated receiving waters, titrate to an electrometric endpoint of pH 3.9, using the procedure in: Annual Book of ASTM Standards, Part 31, "Water", p 115, D-1067, Method D, (1976).

3.4 Oil and grease, by coating the pH electrode, may also interfere, causing sluggish response.

4. Apparatus 4.1 pH meter or electrically operated titrator that uses a glass electrode and can be read to

0.05 pH units. Standardize and calibrate according to manufacturer's instructions. If automatic temperature compensation is not provided, make titration at 25 ±2° C.

4.2 Use an appropriate sized vessel to keep the air space above the solution at a minimum. Use a rubber stopper fitted with holes for the glass electrode, reference electrode (or combination electrode) and buret.

4.3 Magnetic stirrer, pipets, flasks and other standard laboratory equipment. 4.4 Burets, Pyrex 50, 25 and 10 ml.

5. Reagents 5.1 Sodium carbonate solution, approximately 0.05 N: Place 2.5 ±0.2 g (to nearest mg)

Na,CO3 (dried at 250°C for 4 hours and cooled in desiccator) into a 1 liter volumetric flask and dilute to the mark.

Approved for NPDES Issued 1971 Editorial revision 1978

310.1-1

5.2 Standard acid (sulfuric or hydrochloric), 0.1 N: Dilute 3.0 ml conc H2S0, or 8.3 ml cone HC1 to 1 liter with distilled water. Standardize versus 40.0 ml of 0.05 N Na2CO3 solution with about 60 ml distilled water by titrating potentiometrically to pH of about 5. Lift electrode and rinse into beaker. Boil solution gently for 3-5 minutes under a watch glass cover. Cool to room temperature. Rinse cover glass into beaker. Continue titration to the pH inflection point. Calculate normality using:

A x B N — 53.00 x C

where: A = g Na2CO3 weighed into 1 liter B = ml Na2CO3 solution C = ml acid used to inflection point

5.3 Standard acid (sulfuric or hydrochloric), 0.02 N: Dilute 200.0 ml of 0.1000 N standard acid to 1 liter with distilled water. Standardize by potentiometric titration of 15.0 ml 0.05 N Na2CO3 solution as above.

6. Procedure 6.1 Sample size

6.1.1 Use a sufficiently large volume of titrant ( > 20 ml in a 50 ml buret) to obtain good precision while keeping volume low enough to permit sharp end point.

6.1.2 For < 1000 mg CaCO3/1 use 0.02 N titrant 6.1.3 For > 1000 mg CaCO3/1 use 0.1 N titrant 6.1.4 A preliminary titration is helpful.

6.2 Potentiometric titration 6.2.1 Place sample in flask by pipetting with pipet tip near bottom of flask 6.2.2 Measure pH of sample 6.2.3 Add standard acid (5.2 or 5.3), being careful to stir thoroughly but gently to allow

needle to obtain equilibrium. 6.2.4 Titrate to pH 4.5. Record volume of titrant.

6.3 Potentiometric titration of low alkalinity 6.3.1 For alkalinity of < 20 mg/1 titrate 100-200 ml as above (6.2) using a 10 ml

microburet and 0.02 N acid solution (5.3). 6.3.2 Stop titration at pH in range of 4.3-4.7, record volume and exact pH. Very

carefully add titrant to lower pH exactly 0.3 pH units and record volume. 7. Calculations

7.1 Potentiometric titration to pH 4.5

Alkalinity, mg/1 CaCO3 — A xNx 50,000 ml of sample

310.1-2

I

/4

where:

utiou A = ml standard acid

Lift N = normality standard acid

glass 7.2 Potentiometric titration of low alkalinity: -o the

Total alkalinity, mg/1 CaCO3 = (2B - C) x N x 50,000 ml of sample

where: B = ml titrant to first recorded pH C = total ml titrant to reach pH 0.3 units lower N = normality of acid

8. Precision and Accuracy 8.1 Forty analysts in seventeen laboratories analyzed synthetic water samples containing

increments of bicarbonate, with the following results: ndard 11 0.05

Increment as Precision as Accuracy as Alkalinity Standard Deviation Bias, Bias,

mg/liter, CaCO3 mg/liter, CaCO3 mg/I, CaCO3

8 1.27 + 10.61 +0.85 9 1.14 +22.29 +2.0

113 5.28 - 8.19 -9.3 119 5.36 - 7.42 -8.8

good

) allow (FWPCA Method Study 1, Mineral and Physical Analyses)

10 ml

8.2 In a single laboratory (EMSL) using surface water samples at an average concentration of 122 mg CaCO3/1, the standard deviation was t3.

. Very Bibliography

1. Standard Methods for the Examination of Water and Wastewater, 14th Edition, p 278, Method 403, (1975).

2. Annual Book of ASTM Standards, Part 31, "Water", p 113, D-1067, Method B, (1976).

310.1-3

/ /

VIRGINIA POLLUTION ABATEMENT PERMIT APPLICATION

FORM D

MUNICIPAL WASTE

PART C

PART D-V SLUDGE CHARACTERIZATION FORM

1. Facility Name:

'for vg sign t

2. Source or Generator:

3. Type of Treatment:

4. Sludge Treatment Classification:

I certi under

5. Provide at least one analysis for each parameter. Upon review, additional analyses may (Sign; be required by DEQ.

e'srameter Sludge

ent Solids Ale Solids

pN S.U. Alkalinity as CaCO, * mg/kg Calcium Carbonate Equivalence Nitrogen, (Nitrate) m9/1 Nitrogen, (Ammonium) mg/kg Nitrogen, (Total Iceldahl) mg/kg Phosphorus, (Total) mg/kg Potassium, (Total) mg/kg Lead mg/kg Cadmium mg/kg Copper mg/kg Mckel mg/kg Zinc mg/kg Arsenic mg/kg Boron mg/kg Chromium mg/kg Mercury mg/k9 Aluminum mg/kg Chlorides mg/kg Manganese mg/k9 Calcium Sulfates mg/kg Molybdenum mg/kg PCBs mg/k9

* Ume treated sludges (io% or more lime by dry weight should be analyzed for percent CaCO3).

6. Provide at least one analysis of any other pollutants which you believe may be present in

the sludge. Upon review, additional analyses may be required by DEQ.

D-V.1

4. Waste Characterization

a. Wastewater - Provide at least one analysis for each parameter. Upon additional analyses may be required by DEQ.

Parameter Concentration

Flow to treatment MGD Flow to storage MGD Vol. to treatment MG

"Vo1.10 storage MG Vol. Land applied MG/year BOD m9/I COD mg/I TOC mg/I TSS Percent Solids PH S.U. Alkalinity as CaCO3 Nitrogen, (Nitrate) mg/I Nitrogen, (Ammonium) mg/I Nitrogen, (Total Igeldahl) mg/I Phosphorus, (Total) mg/I Potassium, (Total) m9/I Sodium mg/I

mg/1

b. Sludge - Provide at least one analysis for each parameter. Upon review, ad analyses may be required by DEQ.

Parameter Concentration*

Percent Solids Volatile Solids pH S.U. Alkalinity as CaCO3** mg/kg Calcium Carbonate Equivalence mg/kg Nitrogen (Nitrate) Nitrogen (Ammonium) mg/kg Nitrogen (Total igeklahl) mg/kg Phosphorous (Total) mg/kg Potassium (Total) mg/kg Lead mg/kg Cadmium mg/kg Copper mg/kg Nickel mg/kg Zno mg/kg

mg/kg

Unless otherwise noted, report results on dry weight basis.

** Urns treated sludges (IQ% or more lime by dry weight should be analyzed for percent CaCO3).

C-I.3